Horses evolved teeth with a cement covering and evolved from multiple toes to a single hoof because:
a. their diet changed from plants and meat, to just plants.
b. horses have always been the same.
c. their environment changed from forest to grassland as the forests shrank.
d. they became hunted by humans and evolved advantages to run faster.

What best explains whether bromine (br) or neon (ne) is more likely to form a covalent bond? bromine forms covalent bonds because it has seven valence electrons, but neon has eight valence electrons and already fulfills the octet rule. bromine forms covalent bonds because it has many electron shells, but neon has only two electron shells and is tightly bound to its electrons. neon forms covalent bonds because it can share its valence electrons, but bromine has seven valence electrons and can gain only one more electron. neon forms covalent bonds because it has only two electron shells, but bromine has many electron shells and will lose electrons in order to fulfill the octet rule.